When talking to clients, it's always important to make sure that both the client and the stylist are aware of colour theory especially in the day of bright fashion colours!
As a hairdresser, colour theory really starts by understanding exactly how natural hair gets colour. (This will probably give you a better understanding of why hair goes grey as we age too)
Natural hair colour is entirely down to melanin pigments contained within the cortex of the hair.
In human hair, it's important to note that you can find two types of melanin pigment and these are eumelanin and pheomelanin. These two pigments vary in different parts and blend together to create all the wonderful natural hair colours we see day to day without chemical intervention.
To break it down even further into what each pigment does you should know that:
Eumelanin is the pigment that provides the darker shades, your black and brown pigments so this pigment would be the defining factor on how dark the colour of the hair is.
Pheomelanin is the pigment that provides the brighter colours such as your reds and yellow pigments and allows for much warmer tones in thei hair. When higher levels of pheomelanin are present their hair will tend to be Auburn, golden, strawberry or ginger.
The above should be fairly easy to understand once you've managed to memorise the names.
You may be asking though, why hair colour naturally changes over time? As mentioned above, tog may also be asking why natural hair goes grey as we age. Well the answer is partly in the question, Age!
Ageing can affect the levels of pigment production in the hair, simply down to the fact that as our bodies age, the production of melanin starts to slow down and eventually the production of melanin stops alltogether which leads the hair to grow without pigmentation, meaning it grows white/grey.
You may have also observed the opposite occurring naturally as well! You may have noticed that a lot of children are born with fairly light hair, even blonde hair! Which gradually starts to darken into a dark blonde or even a dark brown hair colour. This is down to the increased production of melanin occurring which usually happens around 7 to 8 years old.
There can be a variety of factors that affect the production of melanin and affect pigmentation within the hair, these can be environmental factors or even factors to do with a person's health, medication, pregnancy, illness etc...
Environmental factors that can be taken into account would be things such as humidity and wind bringing more oxygen into the hair. Oxygen attacks the pigments in the hair. Sun can ask accelerate the process. The blue pigments in the hair are broken down the easiest and when they disappear you'll be left with just the warm undertones of red and yellow showing which some of you may have clocked, this is what blue shampoo is for.
Health issues that can affect the hair vary and can include autoimmune illnesses, thyroid disease, vitiligo and ageing syndromes.
Medications can also alter the production of melanin and pigments for example, certain drugs used in the prevention of malwria can lighten hair, whilst on the opposite end, some drugs that are used in the treatment of epilepsy can actually darken the hair!
Lastly, the most common thing I would say we see as hairdressers for the change in hair is...
Pregnancy, many hairdressers, especially hairdressers that have had clients for a long period of time will notice the change in their clients hair when they become pregnant.
Pregnancy can darken light hair dye to the higher levels of the hormone estrogen and progesterone.
You can also notice other changes in the hair during pregnancy also.
